Campag rear mech capacity 13-29 question

still_ill

The only specs I can find on Campag for the rear mech is to use the medium cage if you want a 13-29 rear with a compact. Does anyone know if the only difference in the mech (10 speed Centaur) is the cage length or do they also have a different sweep to cover the 29t cog?

At the moment I have a short cage mech and a 12-25 but for touring I'd like to run a 13-29 for a few weeks. I have a compact at the front but rather than a 34-50 I have a 34-46 (cyclocross bike).

As I work it out the short rear mech is designed to cope with 29t difference (34/50 + 12-25) and the set up I want is only 28t (34/46 + 13-29). So it should all work if the mechs are the same apart from the cage and the short rear mech will clear the 29t cog.

Sorry for the ramble! Opinions?

Monty Dog

Plenty of people successfully run the 13-29 rear mech with a short-arm rear mech. The difference between the short and medium arm mechs is the length of the jockey wheel cape. I would get the cassette and try it first - you'll need to avoid small sprocket / chainring gear combos as there's a risk of the mech hitting the sprockets.

Steve928

As Monty said, plus I occasionally even run a 13-30 cassette on a short cage and all cog combinations are fine - even the very bad big+big won't actually break anything.

Got a picture somewhere.. Here it is:

still_ill

Brilliant thanks, I suspected that would be the case but I am a recent Campag convert!

That does of course mean I dont have an excuse to buy a touring bike now, just a cassette and new chain.